Positive temperature coefficient of resistance resistor/overload (PTCR/OL) assemblies have many uses in industry. The resistance of PTCR/OL assemblies increases with a rise in temperature of the device. Essentially, these assemblies operate normally under normal temperature or electrical current conditions. However, when the ambient temperature in the assemblies or the current flow through the assemblies increases to a level where heat is produced, the resistance of the assemblies increases to limit the flow of current. PTCR/OL assemblies have numerous uses in electronic circuit boards and larger commercial and consumer equipment, such as relays, generators, motors and compressors.
It is desirable to simplify the manufacture of these assemblies and their installation on the equipment of which they comprise a part. Because the equipment in which PTCR/OL assemblies are used is often bulky and heavy, it may be difficult to install the PTCR/OL assembly onto the equipment during manufacture due to size and location restraints. Similarly, removing a failed PTCR/OL assembly and installing a new assembly in situ is often hampered by equipment size and location and the position of the PTCR/OL assembly on the equipment. Thus, the need arose for PTCR/OL assemblies that could be easily installed during equipment manufacture, and easily replaced in situ in the event of a failure.
Because the equipment on which PTCR/OL assemblies are used tend to be subject to vibration, designs have evolved that ensure the assemblies remain securely attached to the equipment, and that connection mechanisms remain securely connected during use, and will not vibrate loose over time. For electrical connections, there is a dual need of making a connection that will remain secure, and keeping electrical connections sufficiently isolated to prevent undesirable contact or short-circuit during operation due to equipment vibration. In order to achieve these operational objectives of ensuring secure connections and proper electrical contact, the electrical connection mechanisms designed are often difficult to install, remove, or reconnect when assembling or replacing the PTCR/OL assembly, and may require the use of special tools.